title: Effects of DRD2/ANKK1 gene variations and clinical factors on aripiprazole efficacy in schizophrenic patients.
abstract: OBJECTIVE
  Aripiprazole, a novel antipsychotic agent, acts as a partial agonist at dopamine D2 receptors (DRD2). We investigate whether its efficacy is predictable by DRD2/ANKK1 gene polymorphisms and clinical factors in Han Chinese hospitalized patients with acutely exacerbated schizophrenia.
  
  
  METHODS
  After hospitalization, the patients (n=128) were given aripiprazole for up to 4 weeks. They were genotyped for four functional DRD2/ANKK1 polymorphisms: -141 Ins/Del, Ser311Cys, C957T, and TaqIA. Clinical factors such as gender, age, illness duration, education level, diagnostic subtype, and medication dosage were also recorded. Psychopathology was measured biweekly with the positive and negative syndrome scale (PANSS). The effects of genetic and clinical factors on PANSS performance upon aripiprazole treatment were analyzed by a mixed modeling approach (SAS Proc MIXED).
  
  
  RESULTS
  Compared to the patients with TaqI A2/A2 genotype, A1 carriers are associated with superior therapeutic response on positive symptoms after 4-week aripiprazole treatment. Regarding the C957T polymorphism, patients with C/C genotype were associated with poor aripiprazole response for excitement symptoms when compared with T/T patients. The other two polymorphisms, -141 Ins/Del, and Ser311Cys, have no significant effects on PANSS performance. The clinical factors including medication dosage, illness duration, and diagnostic subtype could influence PANSS performance upon aripiprazole treatment.
  
  
  CONCLUSIONS
  This study suggests that DRD2/ANKK1 gene variations and some clinical factors may predict individual response to aripiprazole.
authors.affiliation: Department of Psychiatry, Tzu-Chi General Hospital and University, Taiwan. shengmp@so-net.net.tw
authors.forename: Yu-Chih
authors.initials: YC
authors.lastname: Shen
authors.forename: Shih-Fen
authors.initials: SF
authors.lastname: Chen
authors.forename: Chia-Hsiang
authors.initials: CH
authors.lastname: Chen
authors.forename: Chaucer C H
authors.initials: CC
authors.lastname: Lin
authors.forename: Shaw-Ji
authors.initials: SJ
authors.lastname: Chen
authors.forename: Yu-Jung
authors.initials: YJ
authors.lastname: Chen
authors.forename: Sy-Ueng
authors.initials: SU
authors.lastname: Luu
mesh_terms: D000293:Adolescent; D000328:Adult; D014150:Antipsychotic Agents / Q000627:therapeutic use; D000068180:Aripiprazole; D005260:Female; D005500:Follow-Up Studies; D020022:Genetic Predisposition to Disease / Q000235:genetics; D006760:Hospitalization; D006801:Humans; D008297:Male; D008875:Middle Aged; D010879:Piperazines / Q000627:therapeutic use*; D011110:Polymorphism, Genetic / Q000235:genetics*; D017346:Protein Serine-Threonine Kinases / Q000235:genetics*; D011569:Psychiatric Status Rating Scales / Q000706:statistics & numerical data; D015363:Quinolones / Q000627:therapeutic use*; D017448:Receptors, Dopamine D2 / Q000235:genetics*; D012559:Schizophrenia / Q000188:drug therapy* / Q000235:genetics*; D013624:Taiwan; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D014150:Antipsychotic Agents; D010879:Piperazines; D015363:Quinolones; D017448:Receptors, Dopamine D2; D000068180:Aripiprazole; C489948:ANKK1 protein, human; D017346:Protein Serine-Threonine Kinases